A. They obviously pique our sense of beauty, memory, regret, longing, sensuality. And there's this: the "honest signal hypothesis." People may wish to deceive one another for any number of reasons, but music is an honest signal, says McGill University's Daniel J. Levitin in The World in Six Songs.

A person who is singing would be less able to fake emotions, goes the theory. For reasons that aren't fully understood, we seem to be exquisitely sensitive to the emotional state of singers. When someone tells us they love us, we may have our doubts; but when they sing it, all our doubts seem to melt away.

"This may be something beyond our rational control– singing matters." Perhaps this is why people become furious when they find that singers are lip-syncing. It may also explain our fascination with the private lives of rock singers.

"If they are not living the life they profess in their songs, our truth detectors go wild." Real love requires an almost irrational trust and faith in another person, making the link between truth and love a psychological linchpin of human interaction. And it may be why love songs are the most common pop type.

Q. For a young couple who love science, just what might be a doggone dandy of a honeymoon?–M. Curie

A. While many of us might travel domestically and send friends postcards, University of California's Ryan and Corin McLean Boyko visited Africa and sent back samples of dog DNA, according to Science magazine. Between gazing at the pyramids and rafting past crocodiles, the two grad students collected blood samples from 350 village dogs in Uganda, Egypt, and Namibia for a family member's post-doc research project in genetics at Cornell. Armed with a portable centrifuge, the newlyweds got help from veterinarians and government officials for the samplings, weighing each dog in a cloth sling suspended from a fish scale and vaccinating some against rabies. At nightfall, the motor of a hired taxi ran their centrifuge to process the blood samples.

"Science is a big part of our relationship," says Corin, "so it seemed fitting to be doing this for our honeymoon, and we think this will be one of our favorite memories for years to come." In addition, the couple will gain a citation as co-authors of the paper on African dog diversity.

Q. Who was perhaps the dourest prognosticator of the last few centuries, and have we humans successfully beat his gloomy economics yet?–J. Dixon

A. Thomas Robert Malthus was the economist who in 1798 famously predicted that population growth tends to outstrip food production, depressing living standards and pitching the world back toward subsistence, says Jeffrey Sachs in Scientific American magazine.

Yet as advances in seed breeding, chemical fertilizers, irrigation, and the like seemed to buoy the food supply limitlessly, Malthusian economics became a source of mockery. As the population grew, it was argued, more geniuses would appear, spurring technology even more. But the replacement fertility rate of 2.1 kids per family now teeters perilously at 2.6, leading the U.N. Population Division to caution that with the current addition of 79 million people per year, world population may total 9.2 billion by 2050!

The dangers here include food and oil shortages, rising greenhouse gasses, gutting of the oceans, depletion of the rain forests, etc. Yet these are not inevitable, stresses Sachs, if we all take the right steps by converting to solar power and safe nuclear power plus developing water-efficient farming, green buildings, high-mileage cars. We'll also need to rethink our modern diets and lifestyles to reduce consumption.

So have we beaten Malthus? "Two centuries after his work, we still do not really know."

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Send strange questions to brothers Bill and Rich at strangetrue@compuserve.com.